Wireless-communication devices (hereinafter “nodes”) such as cell phones, smart phones, and mobile Wi-Fi hotspots are generally configured with the ability to communicate with other network entities via a wireless network. Well known examples of wireless-communication protocols according to which such wireless networks operate include relatively long-range wireless-communication protocols (e.g., Global System for Mobile Communications (GSM), Long Term Evolution (LTE), and the like), relatively short-range wireless-communication protocols (e.g., Wi-Fi and the like), and/or one or more land mobile radio (LMR) protocols (e.g., European Telecommunications Standards Institute Digital Mobile Radio (ETSI-DMR), Terrestrial Trunked Radio (TETRA), APCO Project 25 (P25), Digital Mobile Radio (DMR), and the like), among numerous other examples.
Nodes in an infrastructure-based wireless network typically communicate over an air interface with a network-dedicated base station such as a base transceiver station (BTS), an eNodeB, a wireless access point, and/or a Wi-Fi router (among other examples). The base station is generally responsible for relaying communication between nodes and/or between other networks (such as the Internet). Respective nodes in an infrastructure-based wireless network typically do not communicate directly with other nodes over an air interface.
An ad-hoc wireless network, in contrast, typically does not include a dedicated base station for relaying communication. Rather, each node in the network functions to relay communication between nodes in the network. A respective node will typically communicate directly with nodes that are within wireless-communication range of the respective node, and will otherwise rely on intermediate nodes to relay communication with network nodes that are not within range of the respective node. Moreover, some nodes can function (often according to various device modes) in both infrastructure-based wireless networks and ad-hoc wireless networks, as is known to those having skill in the relevant art.
Wireless networks, both infrastructure-based and ad-hoc, are susceptible to “collisions”: if more than one node in a wireless network is transmitting at any given time, the interference resulting from the simultaneous transmissions may lead to the loss of the communications in the respective transmissions. In an infrastructure-based wireless network, the base station can coordinate permitted transmission times for the respective network nodes so as to avoid collisions. Because ad-hoc wireless networks operate without such a dedicated entity, a different approach is needed to avoid collisions in such networks. Accordingly, there is a need for methods and systems for node operation according to network-wide resource-allocation schedules.
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The apparatus and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.